Ask The Disease Specialist: Why Is It So Hard To Beat The Plague?

Rat traps are a weapon behind used to fight the plague in Madagascar, since the rodents carry the disease. But getting rid of all the rats would be difficult — and without rats, plague-infected fleas could then turn to humans for a blood meal.

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An outbreak of the plague is growing in Madagascar. Air Seychelles announced that it has canceled all flights into the country after a traveler returned to the Seychelles with the illness — despite World Health Organization guidance against travel restrictions because "the risk of international spread of plague appears very low." WHO has sent enough antibiotics to treat more than 5,000 people who've come down with the disease and a team of five people as well.

We checked in with Dr. Daniel Bausch, a virologist who was deeply involved in the response to the 2014 Ebola epidemic. Now, as director of the UK Public Health Rapid Support Team, he deploys health responders and epidemiologists to places experiencing bad outbreaks. In the last five months, he has sent teams to help tackle bouts of cholera in Ethiopia, meningitis in Nigeria, waterborne diseases in Sierra Leone after some terrible landslides and now plague in Madagascar.

This interview was edited for length and clarity.

It seems like there are a lot of outbreaks these days. Are we just more aware of them, or is something different happening?

I don't know how to answer that with a definitive answer. Does it mean we're getting better at doing our job of surveillance? Is it because there's more contact and interaction between people? Or more communication between people, so we know what's going on? Is it global warming that is influencing things? If you ask me to give you my gestalt opinion — for which I can provide no data whatsoever — I would say it's all of those things. But I don't think that anyone can tell you, "This is the reason why it seems like it's a very active period right now for the planet with outbreaks."

What I will say, unfortunately, is that's not going to go away anytime soon. I think it's going to be an active period for the planet for outbreaks for probably the remainder of our lives.

Uh oh.

I hope not. We're trying to work on that. I think we just need to not lose the vigor that the big Ebola outbreak instilled in us and really make sure we put the systems in place to gain the control that we can.

You just sent two epidemiologists and a clinician to Madagascar. There have now been more than 50 confirmed cases of the plague, and over 300 more unconfirmed cases since the beginning of August. Is that cause for panic?

If you say the names of diseases like "Ebola," "anthrax," "plague," there's going to be a strong response. But we certainly don't need panic in response to the plague outbreak. We have ways to detect cases and to give treatments to people who have the disease and actually even give post-exposure prophylaxis — or antibiotics — to people who may have been exposed.

Plague can be a very serious disease. In contrast to Ebola, which we were talking about so much a few years ago, plague is a bacterium that's sensitive to lots of antibiotics. It's not a disease that's difficult to treat — assuming that you recognize it and get people to treatment.

So panic? Definitely not. Awareness and rapid response? Definitely indicated. And that is what's happening now.

But the Ministry of Health is reporting new cases every day. If plague is easily treatable, why is it spreading in Madagascar right now?

We think it's a mix of different things. There's probably, in the beginning at least, a fair amount of denial. There's also economic disincentives for some people. It costs money to seek health care and if you don't believe that you have a severe disease, maybe you'll say, "Why am I gonna spend money to go seek health care when I'm sure I'll get better soon" and just wait it out. Because in the beginning the plague doesn't seem that different from a cold or other respiratory disease.

And there still can be a stigma — people don't want to be recognized as having the disease.

The avoiding of doctors and health workers — that's something that came up with Ebola, too. So it's not just a Madagascar thing?

How many times have you said to somebody "You know, you really should go see a doctor," and they didn't go see a doctor?

There's lots of different reasons: inconvenience, not liking doctors, fear of what the doctor is going to say, not having time or money. I think you can find those examples in the U.S. and you can find those examples in Madagascar, too.

Plague outbreaks start when infected fleas jump from rats onto humans. Can't they just get rid of all the rats?

I mean with time, I suppose, yes. But that's not going to happen. You have to get rid of all the rodent reservoirs and the small animal reservoirs. That's not an easy thing to do. Take Madagascar out of the equation. You know, can Washington get rid of all its rodents? Probably not. We can cut it down. We can control it to a degree, but I almost guarantee that if you open your eyes here and there, you see rats around Washington. It would require an incredible undertaking that almost no city could do — even much richer cities with more resources.

Can we cut down on the number of rodents and the plague reservoirs and the opportunities for plague to spread to humans? Definitely. That's doable. It just takes a public health will — and resources.

You have to be very careful with plague. It's actually a mistake to just go trap and try to get rid of all the rodents because you get rid of the food source for the fleas, and then they jump on people. So you actually increase the transmission to humans.

If you can't get rid of the rats, what do you think would be the path of least resistance to keeping plague from recurring every year in Madagascar?

It's really more about, if you will, village hygiene. Rodents need something to eat, and so you want to have food stuff and garbage that's stored away so that they can't get into that. So you limit the interaction of rodents with humans because they don't have things to eat in and around your home.

But if you are pretty poor — not everyone in Madagascar is, but some people are — things like storing your food out of reach of rodents and not having any garbage around your house isn't necessarily a given.

That reminds me of how, during the spread of the Zika virus in Brazil, it sounded easy to tell everyone to dump out standing water around their homes to get rid of mosquitoes that carry the disease.

Exactly. If you have a faucet in your house, it seems pretty straightforward to say, "Just get rid of all the standing water because that's where the mosquitoes breed." But if you don't have a working faucet that comes in your house, how do you manage that? It's not that people are stupid or that they can't follow directions.

It sounds like in the near future, Madagascar is stuck with expecting a certain number of plague cases each year — and the risk of this scale of pneumonic plague outbreak happening again.

I think that's true.

I think at this particular time, we need to sort one thing at a time. And the first one is, of course, finding the sick people and getting them treatment and preventing transmission of pneumonic plague]. Quickly on the tails of that, we do need a broader public health response that can limit plague outbreaks from season to season and from year to year. But that's not simple. And resources are always limited.

For example, I have had over the years many Lassa fever projects in Sierra Leone. It's a hemorrhagic fever virus that's spread by rodents — different rodents than the ones we're talking about for plague. I've been working on this for 20 years in Sierra Leone, and when you go to see the chief medical officer, there's a row of chairs outside his office. You get in that line, and when it's your turn, you go in and say, "Look, you have this Lassa fever problem in the southeastern part of the country and we really need to invest in this, and these are the things that need to be done." And you're speaking very earnestly and he's responding earnestly.

But then I come out and look down at the line of chairs. The next one is going to go in and say "we have this TB problem" and the next one is going to say "we have this HIV problem" and the next one "we have this malaria problem."

It's easy when we see the emergency to say, "People are so stupid. Why didn't they handle the rodents so they wouldn't have this problem?" But, of course, you know these are the challenges that the public health administrators and ministers of health and research are faced with everyday: How do you balance the many, many needs and the always limited resources?

At the end of the day, the reason plague becomes a problem is poverty, which is beyond anyone's individual choices or behavior.

I think that's well said. Every lecture I give these days, my last slide is this one about something that I published related to Ebola as a human rights problem, just to make the point that biomedical advances and technology are great. But we have to recognize that until we have a bit more of a just world where everyone has access to [those advances] that they won't completely solve the problem.

So I think we have to be advocates as well as scientists.

Rae Ellen Bichell is a science journalist based in Colorado. She previously covered general science and biomedical research for NPR. You can find her on Twitter @raelnb